1. Field of the Invention
Methods and apparatuses consistent with the present invention relate to a beacon scheduling in a network system. More particularly, the present invention relates to a beacon scheduling method of a router in a network system to prevent beacon conflict.
2. Description of the Related Art
In a ZigBee network topology, nodes in a network system are divided into a ZigBee coordinator (ZC), a ZigBee router (ZR), and a ZigBee device (ZD).
The ZC is on the top of a tree structure and responsible for managing the tree. The ZR is below the ZC and responsible for relaying a beacon transmitted from the ZC to its children (i.e., ZDs) so that the tree structure can be expanded.
The ZD is at the bottom of the network topology. The ZD synchronizes using the beacon transmitted from the ZR and the ZC, and performs communications.
To form such a tree structure, ZRs need to relay beacons received from ZCs to their children. At this time, if the ZRs randomly select a transmission time of the beacons, the beacons are subject to collisions at the child. These beacon collisions block the communications between the nodes.